No heating downstairs

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Hi. Just moved into a home with Tado. 2x wired thermostat, one bridge, one extension. Boiler is potterton, not combi we have a tank.

When we moved in no internet bridge. Tado gave us a workaround. Heating upstairs was fine intermittent downstairs.

Bought a new bridge, all installed and connected. App can control all zones but no heating downstairs even though thermostat and app are set for it to be on. Please help